Applications of a Chemiluminescent Nitrogen

HPLC Detector to the Analysis of Soy Bean Products

PittCon 2004Chicago, IL

Mark E. Homan, R&D Chemist

Examples of Commercially Available Soy Sauce Products

• Chinese Style– (made primarily from soy beans)

• Japanese Style Tamari– (made primarily from soy beans)

• Japanese Style Shoyu– (made from equal mix of soy and wheat)

• Japanese Style Shiro– (made primarily wheat)

• Non-brewed and Semi-brewed– (soy acid hydrolysate)

• Teriyaki (soy sauce principle flavor component)

• Worcestershire (added as flavor component)

• Dipping and traditional Western style sauces

press filterpasteurizationbottling

Naturally Brewed Soy Sauce

soy beans wheatcooking roasting

starterculture

Koji

fermentation

18-20% brine solution,second culture added

Moromi

fermentation 3-12 months

2-3 days

aspergillusoryzae

lactic acid bacteriaand yeast

Chemically Processed Soy Sauce

defatted, soy bean flakes

hydrochloric acid hydrolysis

soy bean hydrolysate

salt, corn syrup, caramel coloring, ethyl alcohol

3-24 hours

+

pasturizationbottling

soy beans + whole wheat

fermentation

sugars

alcohols

amino acids +peptides

organic acids

colorcomponents(i.e. melanin)

aromacomponents

Compounds in Traditionally Brewed Soy Sauce

• Proteins, peptides and amino acids contain nitrogen• Detector responds only to chemically bound nitrogen• Detector response is directly proportional to the total

amount of nitrogen in sample• Calibration with as few as one standard• Total nitrogen or speciated detection modes• Stand alone operation or as a part of a multiple detector

system

Antek Model 8060Chemiluminescent Nitrogen Detector

(CLND)

Sample Type Production Method

Soy bean hydrolysate powder Acid HydrolysisStore Label Brand Acid HydrolysisChinese Dark (wheat + soy) FermentationJapanese Shoyu (wheat + soy)FermentationJapanese Tamari (mostly soy) FermentationTeriyaki (wheat and soy) FermentationWorcestershire (wheat and soy) Unknown

Samples

Hypersil Duet C18/SCX Column

• Mixed mode column (150mm x 2.1mm)– Reversed Phase1

• ala,his,pro,val,met,tyr,lll,leu,phe,trp– Cation Exchange1

• asp,glu,cys,ser,thr,gly,lys,arg

• Elution conditions1– flow rate – 200 µl/min– solvent A – water – solvent B – 80/10/10 water/MeOH/THF + 4% TFA– gradient0-10 min 5%B 40-45 min 80%B to 95%B10-30 min 5%B to 10%B 45-50 min 95%B to 5%B30-40 min 10%B to 80%B

1.) H. J. Chaves Das Neves, American Biotechnology Laboratory, Sept. 1999

Soy Hydrolysate, 1g/100ml

min5 10 15 20 25 30 35 40 45

Norm.

25

50

75

100

125

150

175

200

225

asp

glu

ser

ala

tyr

val

phe his

arg

min5 10 15 20 25 30 35 40 45

Soy Hydrolysate

Store Label Brand

Japanese Tamari

Brewed Versus Processed Soy Sauce Nitrogen Profiles

min0 1 2 3 4 5

Soy Hydrolysate

Store Label Brand

Japanese Tamari

Brewed Versus Processed Soy Sauce Nitrogen Profiles

Vydac Proteins and Peptides C18 Column

• Column 150mm x 2.1mm• Ion pairing reagent heptafluorobutyric acid (HFBA)

• Elution conditions– flow rate – 100µl/min– solvent A – water + 0.05% TFA +0.2% HFAB– solvent B – methanol + 0.1% TFA– gradient

• 0-5 min 1%B• 5-20 min 1%B to 90%B• 20-25 min 90%B• 25-30 min 90%B to 1%B

Soy Bean Acid Hydrolysate 1g/100ml

min5 10 15 20 25

mV

0

200

400

600

800

1000

ser,g

ly,a

snas

pgl

n

glu,

thr

pro

lys

his

val,m

et

tyr,a

rg

cys,

ala ill leu

phe

typ

Store Label Brand Soy Sauce, 1/20 dilution

min5 10 15 20 25

mV

0

100

200

300

400

500

ser,g

ly,a

sn

asp

gln

glu,

thr

pro lys

his

val,m

et

tyr,a

rg

cys,

ala ill le

uph

ety

p

Hydrolysate and Non-brewed Soy Sauce

min5 10 15 20 25

mV

0

200

400

600

800

1000

ser,g

ly,a

sn

asp

gln

glu,

thr

pro

lys

his

val,m

et

tyr,a

rg

cys,

ala ill leu

phe ty

p

Non-brewed,store label brand

Hydrolysate

Chinese Dark Soy Sauce, 1/20 dilution

min5 10 15 20 25

mV

20

40

60

80

100

120

140

160

180

ser,g

ly,a

snas

pgl

n

glu,

thr

pro

lys

his

val,m

et

arg,

tyr

cys,

ala ill leu

phe

typ

Japanese Shoyu Soy Sauce, 1/20 dilution

min5 10 15 20 25

mV

0

100

200

300

400

500

600

ser,g

ly,a

sn

asp,

gln

glu,

thr

pro

lys

his

val,m

et

tyr,a

rgill le

uph

e

ala

typ

Japanese Tamari Soy Sauce, 1/20 dilution

min5 10 15 20 25

mV

0

100

200

300

400

500

600

700

800

ser,g

ly,a

sn

asp,

gln

glu,

thr

pro

lys,

his va

l,met

tyr,a

rg

cys,

ala ill leu

phe

typ

Tamari and Shoyu

0

min5 10 15 20 25

mV

100

200

300

400

500

600

Tamari

Shoyu

Chinese and Tamari

0

min5 10 15 20 25

mV

100

200

300

400

500

600

Chinese

Tamari

Teriyaki Sauce 1/20 dilution

min5 10 15 20 25

Norm.

50

100

150

200

250

300

350

Worcestershire Sauce 1/20 dilution

min5 10 15 20 25

Norm.

25

30

35

40

45

50

55

60

65

Worcestershire Powder 0.5g/100ml

min5 10 15 20 25

Norm.

25

50

75

100

125

150

175

200

225

monosodium glutamate

0500

100015002000250030003500

0 20 40 60 80 100 120

Name N conc area

  (ngN/ul)  

glu 13.2 446.5

phe 13.6 457.8

ala 24.3 821

ser 23.3 786

tyr 17.4 570.7

his 65.1 2211

asp 22.8 764

val 28.3 935

trp 28.7 951

arg 95.9 3110

met 57.7 1988

gln 50 1641

lle 8.5 284.1

lys 47.8 1660

gly 74.5 2509

cys 6.4 182.9

leu 28.6 934.5

pro 87.5 2721

thr 52 1770.9

asn 38.05 1296.5

Detector Calibration Using 20 Common Amino Acids

min5 10 15 20 25

mV

25

50

75

100

125

150

175

200

ADC1 B, CLND (02254\CALMIX2.D)

min5 10 15 20 25

mV

25

50

75

100

125

150

175

200

225

ADC1 B, CLND (02254\CALMIX.D)

Multi-point Nitrogen Calibration Curves From Single Chromatograms

Amino Acid QuantificationSoy Hydrolysate 1g/100ml

min5 10 15 20 25

Norm.

0

200

400

600

800

1000

Amino acids, (mg/g hydrolysate)ser \ glu \ lys 46.5 arg 47.6gly 135 thr — 117 his 12.3 ill 33.5asn / ala 61.6 val 29.6 leu 48.0asp 44.5 cys 0 met 7.5 phe 33.0gln 25.7 pro 18.0 tyr 24.1 trp 0.7

ser,g

ly,a

snas

pgl

n

glu,

thr

pro

lys

his

val,m

et

tyr,a

rg

cys,

ala ill leu ph

etrp

Sample Total Protein Amino Acid Label ProteinName Nitrogen Content Content Information (g/L) (gP/15ml) (gAA/15ml) (gP/15ml)

Japanese Shoyu 17.0 1.451 1.15 2

Japanese Tamari 22.6 1.931 1.46 2

Store Label Brand 14.8 1.271 1.00 1

Chinese Dark 4.62 0.401 0.25 1

From Analysis From LabelSoy Hydrolysate Total Amino Acid Total Amino Acid

Nitrogen Nitrogen Nitrogen Nitrogen13.1%N 10.9%N ~12.6%N ~8.9%N

Total and Amino Acid Nitrogen Analysis

1) A nitrogen conversion factor of 5.71 was used to convert total nitrogen to protein content.Source "Amino Acid Content of Food and Biological Data on proteins", FAO NutritionalStudies No. 24, FAO, Rome, 1970.